High severity · published Jan 15, 2026
CVE-2026-22803
SvelteKit has a memory amplification DoS in Remote Functions binary form deserializer
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KI
kit · sveltejs
>= 2.49.0, < 2.49.5 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-22803
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-22803
Patch
https://github.com/sveltejs/kit/commit/8ed8155215b9a74012fecffb942ad9a793b274e5
Release Notes
https://github.com/sveltejs/kit/releases/tag/@sveltejs%2Fadapter-node@5.5.1
Vendor Advisory
https://github.com/sveltejs/kit/security/advisories/GHSA-j2f3-wq62-6q46
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